Semiconductor device having trench filled up with gate electrode

A semiconductor device comprising:

• a semiconductor substrate that comprises a principal surface and a back surface opposite to the principal surface, wherein the semiconductor substrate further comprises a first semiconductor region on a side of the principal surface, a second semiconductor region that vertically and laterally encompasses the first semiconductor region and a third semiconductor region that vertically and laterally encompasses the second semiconductor region;
• a trench disposed on the side of the principal surface, wherein the trench has a contour that laterally traverses from the first semiconductor region through the second semiconductor region and into the third semiconductor region;
• a gate electrode for filling the trench;
• a MOS structure formed on a sidewall of the trench, wherein the MOS structure has a channel width defined along a depth direction of the semiconductor substrate;
• and
• wherein the second semiconductor region is an epitaxial layer.

A semiconductor device comprising:

• a semiconductor substrate that comprises a principal surface and a back surface opposite to the principal surface, wherein the semiconductor substrate further comprises a source region on a side of the principal surface, a base region that vertically and laterally encompasses the source region, a drift region that vertically and laterally encompasses the base semiconductor region and a drain region disposed on a side of the back surface;
• a trench disposed on the side of the principal surface, wherein the trench has a contour that laterally traverses from the source region through the base region and into the drift semiconductor region;
• a gate electrode for filling the trench;
• and
• a MOS structure formed on a sidewall of the trench, wherein the MOS structure has a channel width defined along a depth direction of the semiconductor substrate.

A semiconductor device comprising:

• a semiconductor substrate having a principal surface and a back surface being an opposite surface of the principal surface;
• a base region of a first conductivity type provided in the semiconductor substrate and extending from the principal surface in a first direction perpendicular to the principal surface;
• a source region of a second conductivity type provided in the base region and extending from the principal surface in the first direction;
• a drift region provided in the semiconductor substrate at an opposite side of the base region with respect to the source region;
• a drain region of the second conductivity type provided in the semiconductor substrate at a location remote from the base region;
• a trench dug from the principal surface and penetrating the base region from the source region, in a second direction parallel to the principal surface;
• a gate insulating film provided on a surface of the trench;
• a gate electrode filling the trench through the gate insulating film;
• a source electrode electrically connected to the source region and the base region;
• and
• a drain electrode electrically connected to the drain region,
• wherein the drift region, the base region and the source region respectively have impurity concentrations, each of which is substantially uniform in the first direction.

A semiconductor device comprising:

• a semiconductor substrate having a principal surface and a back surface being an opposite surface of the principal surface;
• a base region of a first conductivity type provided in the semiconductor substrate and extending from the principal surface in a first direction perpendicular to the principal surface;
• a source region of a second conductivity type provided in the base region and extending from the principal surface in the first direction;
• a drift region provided in the semiconductor substrate at an opposite side of the base region with respect to the source region;
• a drain region of the second conductivity type provided in the semiconductor substrate at a location remote from the base region;
• a trench dug from the principal surface, extending in the first direction, and penetrating the base region from the source region in a second direction;
• a gate insulating film provided on a surface of the trench;
• a gate electrode filling the trench through the gate insulating film;
• a source electrode electrically connected to the source region and the base region;
• and
• a drain electrode electrically connected to the drain region,
• wherein the drift region, the base region and the source region respectively have impurity concentrations, each of which is substantially uniform in the first direction.

A semiconductor device comprising:

• a semiconductor substrate having a principal surface and a back surface being an opposite surface of the principal surface;
• a base region of a first conductivity type provided in the semiconductor substrate and extending from the principal surface in a first direction perpendicular to the principal surface;
• a source region of a second conductivity type provided in the base region and extending from the principal surface in the first direction;
• a drift region provided in the semiconductor substrate at an opposite side of the base region with respect to the source region;
• a drain region of the second conductivity type provided in the semiconductor substrate at a location remote from the base region;
• a trench dug from the principal surface and penetrating the base region from the source region in a second direction parallel to the principal surface;
• a gate insulating film provided on a surface of the trench;
• a gate electrode filling the trench through the gate insulating film;
• a source electrode electrically connected to the source region and the base region;
• a drain electrode electrically connected to the drain region;
• and
• a channel region formed in a portion of the base region adjoining the trench so that a current flows in the channel region in the second direction when a voltage is applied to the gate electrode, the channel region having a width in the first direction that corresponds to a depth direction of the trench.

A semiconductor device comprising:

• a semiconductor substrate of a first conductivity type, having a principal surface and a back surface at an opposite side of the principal surface;
• a source region of a second conductivity type provided in the semiconductor substrate and extending from the principal surface in a first direction perpendicular to the principal surface;
• a drain region of the second conductivity type provided in the semiconductor substrate at a location remote from the source region;
• a trench dug from the principal surface and extending from the source region to the drain region in a second direction;
• a gate insulating film provided on a surface of the trench;
• a gate electrode filling the trench through the gate insulating film;
• a source electrode electrically connected to the source region;
• and
• a drain electrode electrically connected to the drain region,
• wherein the source region, the base region and the drain region respectively have impurity concentrations, each of which is substantially uniform in the first direction;
• and
• wherein, when a voltage is applied to the gate electrode, a channel region is formed in a portion of the semiconductor substrate adjoining the trench, the channel region having a channel width in a depth direction of the trench so as to allow a current to flow therein in a direction parallel to the principal surface.

A semiconductor device comprising:

• a semiconductor substrate having a principal surface and a back surface being an opposite surface of the principal surface;
• a first conductivity type base region extending in the semiconductor substrate from the principal surface in a first direction perpendicular to the principal surface;
• a second conductivity type source region extending in the base region from the principal surface in the first direction;
• a drift region provided at an opposite side of the base region with respect to the source region;
• a second conductivity type drain region extending in the semiconductor substrate from the principal surface in the first direction separately from the base region;
• a trench dug from the principal surface and penetrating the base region from the source region in a second direction parallel to the principal surface;
• a gate insulating film provided on a surface of the trench;
• a gate electrode provided on a surface of the gate insulating film;
• a source electrode electrically connected to the source region and the base region;
• a drain electrode electrically connected to the drain region,
• wherein the drift region, the base region, the source region, and the drain region respectively have impurity concentrations, each of which is substantially uniform in a depth direction of the semiconductor substrate.

A semiconductor device comprising:

• a semiconductor substrate having a principal surface and a back surface being an opposite surface of the principal surface;
• a first conductivity type base region extending in the semiconductor substrate from the principal surface in a first direction perpendicular to the principal surface;
• a second conductivity type source region extending in the base region from the principal surface in the first direction;
• a drift region provided at an opposite side of the base region with respect to the source region;
• a second conductivity type drain region extending in the semiconductor substrate from the principal surface in the first direction separately from the base region;
• a trench dug from the principal surface, extending in the semiconductor substrate in the first direction, and penetrating the base region from the source region in a second direction;
• a gate insulating film provided on a surface of the trench;
• a gate electrode provided on a surface of the gate insulating film;
• a source electrode electrically connected to the source region and the base region;
• and
• a drain electrode electrically connected to the drain region,
• wherein the drift region, the base region, the source region, and the drain region respectively have impurity concentrations, each of which is uniform in a depth direction of the semiconductor substrate.